As one of the two people working on something similar to Heroku or GAE (we're called ep.io), Beanstalk is simultaneously worrying and quite interesting - while it is an interesting player into the market, it's not _that_ hands-off, from what I can see, especially when it comes to databases, or things like Redis, which it's nice to have managed for you as well.

It's possible we'll see people springing up on EC2 offering those as separate services, however.

The other interesting part is that, since they don't do shared hosting but make you use a whole EC2 instance, there's potential for it to cost considerably more for smaller sites, but only once you get past that free plan of theirs (then again, the disk I/O on the Micro instances is truly awful)